In order to reduce a torque to be applied to a tilt shaft of a tilting table device, publications of Patent Documents 1 and 2 each disclose a configuration provided with a torque balance device. The torque balance device includes a first rotary member provided at the tilt shaft, a second rotary member provided at a body frame, a fluid-pressure cylinder device, and a crank mechanism which converts an urging force of the fluid-pressure cylinder device into a rotational force of the second rotary member. The rotary force of the second rotary member caused by the urging force of the fluid-pressure cylinder device via the crank mechanism is transmitted to the first rotary member through meshing of gears, or through a rotation transmitting device, such as a timing belt or a chain, so that a torque in an opposite direction to that of the torque caused by the gravity of the table is applied to the tilt shaft, thereby reducing a torque to be applied to the tilt shaft. Accordingly, when the table is elevated, a load to be applied to a driving motor or a manual handle is reduced, and the table is kept in resting state at an intermediate position between the uppermost position and the lowermost position. Thus, when the table is kept at a predetermined tilt angle, loads to be applied to a rotation transmitting device, such as a gear, a shaft, and a coupler, to the tilt shaft, and to a clamp device can be reduced. Accordingly, a driving motor of a smaller frame number may be used, and the manual handle can be rotated by a smaller force. Also, the margin of safety of the rotation transmitting device against breakage and wearing is increased to a level equal to or higher than the necessary level, and hence, a member having a smaller rigidity may be used. Also, the clamp device may be a device having a smaller clamping force. Further, torsion of the tilt shaft is reduced, thereby providing highly accurate indexing.
[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2000-301405
[Patent Document 2] Japanese Unexamined Patent Application Publication No. 2005-246522